Well looks like everyone was right
Definitely at a 275 m2 limit on size and the set backs seems about right as per other's comment. Not the end of the world so I've had time to think on it and i'm back at the drawing boards.
While i'm still hoping to customise something that is more suited to my needs. I'm still very much keeping a look out for designs from volume builders that would suffice. The land settles in December and at the end of the day i will need to build something, i can't imagine i'd be too upset even if i had to compromise on what i had in my head.
If it's not too much to ask. I am curious if i'm making any progress with the below. I'm trying to shave some size off everything but i don't think my brain is cut out for adding up numbers and comparing it to the build envelope because i can't tell if i'm back where i started or i'm getting closer.